ㄳ ㅄ ㄵ ㄶ ㄺ ㄽ ㄻ ㄾ ㄼ ㄿ ㅀ

As the Final Consonant

As a general rule you pronounce the first of the pair with the exception of:

ㄺ ㄻ ㄿ

With these cuties you pronounce the second of the pair as if the first was never there.

Within A Word

Actually I really shouldn't have to explain it but if you haven't already figured it out, (don't feel bad if you didn't) you let the sound of the second letter carry over to the next available syllable.
For example:

" 젊은 "

jeol•meun
which is young in English (o joven en el español)

look at you being all nerdy and smart. Pat yourself on the back, you did wonderfully. :D